As we’ve seen over the past few months with the new iMacs, there are times when Apple’s (AAPL) cutting-edge designs are difficult to mass produce inside manufacturing plants. Barron’s on Wednesday points us to a new note written by Jefferies & Company analyst Peter Misek claiming that difficulty in producing the larger screens for Apple’s rumored 4.8-inch iPhone could push its launch date back until June 2014. Earlier rumors have hinted that Apple would try to release its own “phablet” this year to compete with Samsung (005930) and its popular Galaxy Note series that sold well over 15 million total units in 2012. Misek thinks that releasing a larger version of the iPhone will be crucial for Apple because “iPhone 5 sales are decelerating faster than expected and builds have been cut again” from 40 million to 30 million this quarter.